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M > MERLIN > Tonto


This mini forum is intended to provide a simple means of discussion about the Merlin Tonto computer. If you want to share your own experience or memories, or add relevant information about this system: post a message!

  Click Here to add a message in the forum


Saturday 13rd January 2018
''CABBIK'' (England)

Some of the less well-known things about it :-

1) It had a dual micro drive unit as standard which, *shock horror... gasps of disbelief* actually worked and worked well, especially with european manufactured microdrive cartridges that were sold for the Tonto.

2) It was supplied with either a monochrome display (as was the Tonto i used/inherited as a personal home computer - obtained legitamately via BT) which was fairly compact, or a larg-ish colour monitor. Notably, the main PSU was embedded in the monitor and the Tonto has no on/off switch.

3) It was prone, if misused, to PSU failures - this usually happened when people frequently shut down (at the power point) the computer. The computer itself, being a combination telecommunications device/x.25 protocol networked message terminal and application orientated desktop computer, was designed to be left switched on 24/7 (only powered off for mainenance work purposes or relocation) and the monitor could be put to sleep (i.e. the front panel button on the display simple shut off the LT side of the display electronics).

4) The commonly sold matching printer was a usually a Tonto rebranded OKI Microline 192/193 - effectively the OKI Microline equivalents to Epson FX80/100 printers. These were often serial and parallel interface equiped, as as far as printers go, were pretty fine reliable items - the 193 i had outlasted the Tonto by many years and made Seikosha GP series unit look like cheap and nasty junk.

5) Probably the least well known accessory (which was an aftermarket item) was a combination dual floppy drive unit (double-density 3.5 inch items which wrote to a format which was PC readable/writable, and with a couple of bytes rewritten, data could be exchanged via 3.5inch disc with Atari ST computers). This dual drive unit also had a full Centronics interface and a full breakout RS232 interface. I was one of rare beasts who had that mystical almost mythical addon.

Aside from it''s X25 phoneline based message exchange function, it was fully equipped with a good terminal/comms feature built-in the resident firmware, and made a very good BBS access device (which i took a lot of advantage of during cheap rates and weekend rates).

As for the two line cords for the phone and data connections - it would operate just fine using one, since you could $ which line was used for data operations and the phone used line one cord (but you could exploit the second line for additional voice telephony use - assuming you bothered to actually RTFM, which most users i know of never actually bothered to do).

Whilst i never owned any ''ROM Packs'', i had various pieces of official and unofficial software for it on microdrive, some ported from the QL and were ports originating as ICL OPD hacks. One of which included a disassemble which i used frequently to snoop into the complete undocumented firmware.

But the rarest (because everyone seemed to mislay them) common part was the formatter microdrive - yeah, you had to use a microdrive cartridge to format a blank cart. Needless to say, since i had about twenty sets of four-pack blank sets, i made various dupes of the software carts and formatter cart and had them stashed for safe keeping and NEVER used an original as a working copy.

All in all, a very pleasant machine to use for it''s comms/telephony/application workstation designed use - it''s usefulness far outweighed it''s flaws, at least in the eyes of this extreme user (i did 90$ of my documentation using it, and used it to prepare plain ascii files for Ventura and Postscript with it, since it was far more comfortable for extended use than the machine i was supposed to use for work).

It probably looks and feels to anyone today like a mutant crossbreed of a games console and a toy kiddy typewriter with a display, but it (and in OPD guise) was definately a bit of an unappreciated landmark in the history of the transition of comms from electro-mechanical TTY (such as teleprinters) towards the more ''domestic'' non-Telex use of electronic tty comms. I fondly remember it for that, as much as i fondly remember the Puma and Cheetah teleprinters as landmarks (in Telex terms) the transitional era of computer-technology based teleprinters.

Now if that doesn''t reveal my aged former 80s computer kiddie status..... :)

Sunday 11th September 2011
Erik N (Australia)

I remember these - saw one in a telecom museum some years ago.
It was a rebadged Tonto obviously for Australian Telecom and had two phone plugs - one for a voice line and one for data AFAIK - if you got a crossed line it would spit out garbage on screen or $ the connection (randomly between the two)
you needed two phone lines to use one - so you had to be pretty rich.

Monday 15th December 2008
Pete (UK)

Hello all,

I have recently acquired a BT promotional video for the Tonto, dated 29-4-1985.
This gives the prices for the Tonto at is launch.

£1245 Basic Mono Machine
£1375 Basic Mono Machine with Xchange
£1675 Colour Machine
£1805 Colour Machine with Xchange
These are all Excluding VAT.

So these are the final prices.
£1462 Basic Mono Machine
£1615 Basic Mono Machine with Xchange
£1968 Colour Machine
£2120 Colour Machine with Xchange

Then you had an optional printer and many optional ROM packs.
This was quite an expensive piece of desk accessory in its day.


Friday 21st March 2008
Peter Hurst (UK)

I worked in BT Datacomms support in the late 80's and early 90's and we all had Tonto's until BT started rebadging Zenith PC's. Although they were quite compact and pretty for the time (!) they sufferred from odd software glitches.

An ex-colleague Bob Calvert (hi Bob!) was a veritable expert on these machines an maintains it was one of the earliest tru multitasking cheap computers and he wrote several programs for it. The rompacks were great, Quill I found OK but the tapes were the weak point.

The Tonto bettered the QL in having a built in V21/V23 modem so you could use it to connect to Prestel and other online services. I can't remember the phone application well but I think it was actually quite good when it worked but again suffered glitches due (?) to multitasking.

Thursday 20th December 2007
Rob Kay (UK)

I set up a network of five One Per Desks in 1985 to link the different operating premises of Salford NHS Community Learning Disability services. I loved the fact that you didnt need to be an expert to set it up: it was simple, just plug and play. The machines were designed for my admin staff, and whilst being typists they were baffled by the word processing capabilities of OPD, the (male) community nurses and social workers couldn't keep their fingers off them so I became the first victim of cyber-slacking! Personally I loved this lightweight machine and mastered all the software functions including mailmerge, and still cant figure out why keyboards don't have integral phones - its so simple and convenient. I was able to save half a secretary/PA by typing my own memos. A pretty good return on my investment!

Thursday 11th October 2007
bill Perry (UK)

These were sold through BT local area sales as well as into bigger projects through BT Field Services. The bigger projects included Customs & Excise at ports and the Home Office Prison Services (HOPS) project. The tape drives were unreliable!

Wednesday 10th October 2007
QUANTA web master (UK)
OPD / Tonto section of the QUANTA web site

I have compiled some useful information on the OPD / Tonto, which can be found on the QUANTA web site.

QUANTA supports QL and related systems, and I
am responsible for maintaining the societies web site.

If anyone would like to donate their OPD / Tonto to QUANTA, or would like to support, documentation
or advice, please get in touch.

We can offer a small sum for surplus OPD / Tonto
hardware and accessories, which we donate to
the Red Cross.

We are trying to establish an OPD / Tonto support network, so that enthusiasts can swap software,
trade hardware and keep this machine alive.

We are in the process of scanning in manuals and documentation for the OPD, establishing an OPD software library and list of frequently asked questions (FAQs).

FAQs will include : where to obtain OPD software,
tips for repairing damaged monitors, suggestions for troubleshooting hardware faults and advice on exchanging files with a PC or Sinclair QL.

Monday 18th September 2006
Tony Woodrow (UK)

This computer was introduced to the majority of Bingo Halls in the mid 80's to introduce "The National Bingo Game", where prizes were up to £50,000, I salvaged two from from two clubs that closed down in South Wales. Alas The monitors no longer work, and I'm looking to getting them working again for "old times sake!"

Wednesday 28th December 2005
dermot hollingsworth (england)

does anyone want to buy a BT MERLIN TONTO in the original case

Saturday 27th December 2003
Jaume (Spain)

this computer don´t sell very well in spain because the word "tonto" in spanish means "idiot"

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